Motion transfer mechanism

ABSTRACT

A plate has a circular opening and diametrically opposed pins extending into the opening. A diaphragm is secured to one face of the plate and covers the opening. Secured to the diaphragm in the center of the opening is a disclike element with portions which nest on and slidably engage the pins. A tongue extending from the disc is actuated to rock the disc, and thereby effect rotational movement of a member secured to the other surface of the diaphragm. Such element may be a pin, or it may be a similar disc which is similarly positioned on pins in an opening of another plate abutting the other surface of the diaphragm.

United States Patent [72] Inventor Allen V. C. Davis 5600 Alta Canyada,La Canada, Calif. 91011 [21] App1.No. 850,787 [22] Filed Aug. 18, 1969[45 Patented Feb. 23, 1971 [54] MOTION TRANSFER MECHANISM 9 Claims, 6Drawing Figs.

[5 2] U.S. Cl 200/172, 74/18 [51] lnt.Cl H01n 3/04 [50] Field of Search200/172 (A), 168 (G), 83.34, 83.91; 74/17.8, 18, 18.1

[56] References Cited UNITED STATES PATENTS 3,043,225 7/1962 Nielsen..200/83(.91)(X) 3,210,507 10/1965 Kadisevskis et al 74/18.](X)3,244,849 4/1966 Rauret et al. ZOO/168(6) 3,304,397 2/1967 Bernhagen200/168(G) 3,373,257 3/1968 Matthias et al. ...200/l72(A)(X) PrimaryExaminerl-l. 0. Jones Att0rney-Perry E. Turner ABSTRACT: A plate has acircular opening and diametrically opposed pins extending into theopening. A diaphragm is secured to one face of the plate and covers theopening. Secured to the diaphragm in the center of the opening is adisclike element with portions which nest on and slidably engage thepins. A tongue extending from the disc is actuated to rock the disc, andthereby effect rotational movement of a member secured to the othersurface of the diaphragm. Such element may be a pin, or it may be asimilar disc which is similarly positioned on pins in an opening ofanother plate abutting the other surface of the diaphragm.

MOTION TRANSFER MECHANISM BACKGROUND OF THEINVENTION 1. Field of theInvention I This invention relates to devices for transferring motionthrough a wall via a diaphragm.

2. Description of the Prior Art The frame of reference for thedescription of this invention is a precision switch and actuatingmechanism therefor. In such arrangements, the switch is mounted in ahermetically sealed chamber, one wall of which has an opening covered bya diaphragm. Extending through the diaphragm, and sealed thereto, is aswitch actuating member which is so arranged that pressure applied tothe external portion is transferred through the diaphragm to theinterior portion for actuating the switch.

Such a diaphragm is a flexible membrane which tends to move into and outof the switch chamber when pressure is applied to the operating member,or when there are changes in the pressure differential on the oppositesurfaces of the diaphragm. Because of this characteristic, the pivotalaxis of the switch actuator isnot constant and results in changes in theoperating forces for the switch. Many attempts have been made to providesuch a motion transfer device which does not permit the diaphragm tofloat. In such attempts as heretofore known, however, the devices inoperation set up undesirable stresses in the diaphragm and shorten itslife.

SUMMARY OF THE INVENTION My invention embraces a plate having an openingthrough it, a diaphragm on one surface of the plate covering theopening, an element secured to the diaphragm within the opening, andmean hingedly supporting the element for rotational movement along anaxis in the plane of the diaphragm. My invention also embraces a leveror tongue attached to or integral with the element for impartingrotational movement thereto, and a member fixed to the diaphragmopposite said element for actuation upon'such rotational movement. Withthis arrangement, the diaphragm is prevented from absorbing work andbeing unduly stressed as in the prior art motion transfer devices.

BRIEF DESCRIPTION OF THE DRAWING FIG. 5 is a fragmentary sectional viewtaken along the line I 55 of FIG. 4; and

FIG. 6 is a fragmentary sectional view, similar to FIG. 3, of a modifiedform of motion transfer device of myinvention.

DESCRIPTION OF PREFERRED EMBODIMENTS Referring to FIG. 1, a switch 10 ispositioned in one end of a housing 12. The switch 10 is in ahermetically sealed chamber 14 having an upper wall 16 through whichinterconnected levers or arms 18, 20 function to actuate the plunger ofthe switch 10. An element 22 hearing against the upper arm 18 is adaptedto be actuated by suitable means in the upper end of the housing 12. Ifdesired, of course, a manually operable switch may be provided byeliminating the element 22 and the upper end of the housing 12.

The wall 16 in one form of my invention (see FIGS. 2-5) employs a pairof rigid plates 30 between which a thin, flexible membrane or diaphragm32 is sandwiched. As indicated, the plates 30 and diaphragm 32 are ofthe same diameters, and are secured together at their peripheries as bywelding. Each of the plates 30 has a circular opening 34, and the platesare secured together with their openings 34 aligned.

As best seen in FIG. 2, each plate 30 has a pair of diametricallyopposed pins 36 in the opening 34 thereof. And referring to FIG. 5 alongwith FIGS. 2-4, the pins 36 have confronting flat faces abutting theopposite surfaces of the diaphragm 32. Also, and as best seen in FIG. 5,the pins 36 are shaped with a radius of curvature of a circle having adiameter equal to the combined thicknesses of the plates 30 anddiaphragm 32.

The pins 36 of the plates 30 function like hinge pins for respectiveelements 40 from which the arms 18, 20 extend. The element 40 is shownby way of example in the form of a disc having diametrically opposedportions 42 struck therefrom to slidably and matingly fit the pins 36.With the parts thus formed, the element 40 comes to rest against theadjacent surface of the diaphragm 32 when the struck portions 42 arepositioned on the ends of the pins 36. The center portion, marked x inFIG. 2, is welded to the diaphragm.

With the parts assembled as shown, and with the peripheries of theplates 30 and diaphragm 32 welded to the inner surface of the housing12, thereby to form the upper wall 16 of the hermetically sealed chamber14 as above described, the normally higher pressure above the chambercauses portions of the diaphragm 32 to pouch inwardly. However, sincethe upper element 40 is welded to the diaphragm, and rides on the pins36, no such inner movement of the diaphragm can take place which willcause the arm 20 to actuate the plunger of the switch 10. Furthermore,the element 40 is shaped to be symmetrical with respect to a linethrough the pins 36, whereby the element 40 cannot undergo movementwithout applying a force to the arm 18 thereof.

When a force is applied to the end of the arm 18, the element 40 rockson the pins 36 (clockwise in FIG. 3), and the free portions of thediaphragm, i.e., those portions that are pouched inwardly due to apressure differential, accommodate the motion imparted to the element40. The parts are preferably adjusted so that the plunger of the switch10 is actuated within the range of movement permitted by the diaphragmbefore it becomes taut.

In the embodiment of FIG. 6, the lower element 40 and its arm 20 arereplaced with a headed pin 46. As shown, the head of the pin is weldedto the lower surface of the diaphragm 32, and the shank of the pinengages the plunger of the switch 10. When a force is applied to the arm18, the same rocking movement of the element 40 takes place as abovedescribed for the embodiment of FIGS. 1-5. The corresponding movementimparted to the pin 46 causes the switch 10 to be actuated aspreviously.

It will be apparent that'my invention embraces a variety ofmodifications of the arrangements illustrated and described. Forexample, while it is preferred that the arms 18, 20 extend from theperipheral edges of the elements 40, they may readily be attached to theouter surfaces of the elements and in fact may be welded to the centersthereof. Also, the elements 40 need not be formed with arms 18, 20, butmay be provided with pins which extend vertically therefrom as in themanner of the pin 46 in FIG. 6.

While I have illustrated my invention as one in which the elements 40are slidable on pins 36, it should be noted that my invention embracesany means for supporting the element for rotational movement. Forexample, ball bearings may be mounted on the pins, such bearings havingsemicylindrical inner and outer races. The elements then roll instead ofsliding when they undergo rotational movement. Other means to achieverolling action may also be employed, e.g., one or more wires having oneend of each fixed to the associated plate 30, such wires having freeends interposed between the pins and the portions 42 of the elements.

I claim:

1. In combination:

a plate having an opening therein;

an element positioned in said opening,

said opening being larger than said element;

a diaphragm secured to one surface of said plate and spanning saidopening, said element being secured to said diaphragm; interconnectingmeans on said element and said plate supporting said element forrotational movement along a line in the plane of said diaphragm;

a member secured to said diaphragm opposite to and movable with saidelement; and

an arm attached to said element for effecting rotational movementthereof, said movement being transferred through said diaphragm to saidmember.

2. The combination of claim 1, wherein said interconnecting meansincludes diametrically opposed pins of said plate in said opening andpin mating portions on said element.

3. The combination of claim 2, wherein said pins have flat surfacescoplanar with said one surface of the plate, said pins in cross sectionbeing substantially semicylindrical.

4. The combination of claim 3, including a second plate, said plates anddiaphragm being secured together with the diaphragm between the plates,said second plate having an opening, said plates openings being of thesame dimensions and aligned.

5. The combination of claim 4, wherein said member is identical to saidelement, wherein said second plate has pins in the opening thereof, thepins of both plates being identical and in alignment, and wherein saidmember has pin mating portions identical to those of said element.

6. The combination of claim 4, including:

a switch having a plunger; and

a pin on said member engaging said plunger,

said pin actuating said plunger upon rotational movement of saidelement.

7. The combination of claim 6, wherein said element is disclike, andsaid arm extends from the periphery of said element along a linesubstantially at right angles to the axis of rotational movement of saidelement.

8. The combination of claim 5, including:

a switch having a plunger; and

an arm on said member adapted to actuate said plunger upon rotationalmovement of said element.

9. The combination of claim 2, including bearing means between said pinsand pin mating portions and reliable by said pin mating portions duringrotational movement thereof.

1. In combination: a plate having an opening therein; an elementpositioned in said opening, said opening being larger than said element;a diaphragm secured to one surface of said plate and spanning saidopening, said element being secured to said diaphragm; interconnectingmeans on said element and said plate supporting said element forrotational movement along a line in the plane of said diaphragm; amember secured to said diaphragm opposite to and movable with saidelement; and an arm attached to said element for effecting rotationalmovement thereof, said movement being transferred through said diaphragmto said member.
 2. The combination of claim 1, wherein saidinterconnecting means includes diametrically opposed pins of said platein said opening and pin mating portions on said element.
 3. Thecombination of claim 2, wherein said pins have flat surfaces coplanarwith said one surface of the plate, said pins in cross section beingsubstantially semicylindrical.
 4. The combination of claim 3, includinga second plate, said plates and diaphragm being secured together withthe diaphragm between the plates, said second plate having an opening,said plates openings being of the same dimensions and aligned.
 5. Thecombination of claim 4, wherein said member is identical to saidelement, wherein said second plate has pins in the opening thereof, thepins of both plates being identical and in alignment, and wherein saidmember has pin mating portions identical to those of said element. 6.The combination of claim 4, including: a switch having a plunger; and apin on said member engaging said plunger, said pin actuating saidplunger upon rotational movement of said element.
 7. The combination ofclaim 6, wherein said element is disclike, and said arm extends from theperiphery of said element along a line substantially at right angles tothe axis of rotational movement of said element.
 8. The combination ofclaim 5, including: a switch having a plunger; and an arm on said memberadapted to actuate said plunger upon rotational movement of saidelement.
 9. The combination of claim 2, including bearing means betweensaid pins and pin mating portions and rollable by said pin matingportions during rotational movement thereof.